M
MrMeaner
A couple of days ago I replaced the radiator in the bathroom. I drained the central heating system by isolating water to F/E tank, openind rad bleed valves and draining at lowest point in system.
After installing new rad i closed drain valve and all bleed valves and switched supply back on to F/E tank. Tank filled and I went downstairs to start bleeding rads. Went to bleed, but no air or water coming out. Tried a couple of other rads and same problem. Did a bit of a google and found loads of people with a similar problem with a blocked 'T' above the pump. Our system is quite old, and rather than a 'T' it has a cylinder about the size of a mug. It has three branches, one if the expansion pipe that goes back into the F/E tank, one goes to the top of the pump, and then has the cold feed going into it, and it has a return I am guessing from the boiler. Anyway, after cutting the cold feed it was clear there was a solid blockage which was preventing water from flowing to the pump and the system filling. After a couple of hours I removed thesmall cylinder type device, rmoved the rubbish that had been drawn down from the F/E tank when I was draining the system and replaced it. At the same time I also cleaned and emptied the F/E tank and the cold feed pipe form the F/E tank to the point at which I cut it.
I then filled the system and bled all the rads. Everything was going fine up until this point. Having satisfied myself that I had got rid of all the air I could I switched on the controls for the heating and hot water and fired up the boiler (Potterton Promax 30 HE Plus).
The boiler failed to ignite, in fact it failed to even try. The pump seemed to be working ok, water trickles out if I undo the screw on the end of the pump, and it is not making an unusual noises.
After a minute or so I get the three LED's lit up and flashing on the boiler. The comination indicated the boiler has shut off due to poor or no water flow.
At this point I go to the top of the boiler and open the drain cock on the flow, thinking maybe there is an airlock. After fully opening water barely trickles out at all. I get about a drip per second.
Any suggestions? I was tempted to connected a hose to the drain cock above the boiler and connect this to the mains and possible clear the air block this way. Or have I missed something else? The manual vent next to the cylinder was bled and water comes out when you unscrew it. The MV also appears to be working judging by the motorised noise I hear when I fire up the heating or hotwater.
Any help greatly appreciated.
Thanks
After installing new rad i closed drain valve and all bleed valves and switched supply back on to F/E tank. Tank filled and I went downstairs to start bleeding rads. Went to bleed, but no air or water coming out. Tried a couple of other rads and same problem. Did a bit of a google and found loads of people with a similar problem with a blocked 'T' above the pump. Our system is quite old, and rather than a 'T' it has a cylinder about the size of a mug. It has three branches, one if the expansion pipe that goes back into the F/E tank, one goes to the top of the pump, and then has the cold feed going into it, and it has a return I am guessing from the boiler. Anyway, after cutting the cold feed it was clear there was a solid blockage which was preventing water from flowing to the pump and the system filling. After a couple of hours I removed thesmall cylinder type device, rmoved the rubbish that had been drawn down from the F/E tank when I was draining the system and replaced it. At the same time I also cleaned and emptied the F/E tank and the cold feed pipe form the F/E tank to the point at which I cut it.
I then filled the system and bled all the rads. Everything was going fine up until this point. Having satisfied myself that I had got rid of all the air I could I switched on the controls for the heating and hot water and fired up the boiler (Potterton Promax 30 HE Plus).
The boiler failed to ignite, in fact it failed to even try. The pump seemed to be working ok, water trickles out if I undo the screw on the end of the pump, and it is not making an unusual noises.
After a minute or so I get the three LED's lit up and flashing on the boiler. The comination indicated the boiler has shut off due to poor or no water flow.
At this point I go to the top of the boiler and open the drain cock on the flow, thinking maybe there is an airlock. After fully opening water barely trickles out at all. I get about a drip per second.
Any suggestions? I was tempted to connected a hose to the drain cock above the boiler and connect this to the mains and possible clear the air block this way. Or have I missed something else? The manual vent next to the cylinder was bled and water comes out when you unscrew it. The MV also appears to be working judging by the motorised noise I hear when I fire up the heating or hotwater.
Any help greatly appreciated.
Thanks
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